The present invention is in the field of data processing and more particularly relates to data terminals having a display.
Data terminals generally incorporate a display for providing a visual indication to the operator of selected data. Typically, such a display has the form of a cathode ray tube (CRT) or other type of planar display, such as a liquid crystal display (LCD). A specific point on the display is often indicated to the operator by way of a localized illuminated region, referred to as a cursor. In many applications, for example, in data entry which might occur during a word processing operation, the cursor may be moved by the operator to any desired point on the display.
In the prior art, the positioning control for the cursor is typically provided by keys which must be manually depressed by the operator. Such keys are awkward because they must typically be hit multiple times to move the cursor across the screen. Another way to position a cursor is by use of a "mouse" or joystick. All of these approaches generally required the operator to move his hands from the normal keyboard position. As a result, the operator must re-position his hands with respect to the keys following the desired positioning of the cursor. These special motions to establish cursor control take time, and my lead to user errors which correspondingly reduce the efficiency of the operator interaction with the or a data processing system coupled to the terminal.
In the aviation field, it is known to use optical source and sensor pairs, one of each pair being coupled to a pilots's head and the other coupled to a fixed reference, so that the line-of-sight of the pilot can be tracked, eliminating the necessity of identifying a particular location by hand. See for example, U.S. Pat. Nos. 4,209,255 and and 3,917,412. However, while the latter patents disclose systems for tracking an operator's head motion, there is no disclosure of hands-free cursor control for a data terminal. Moreover, all motions of the operator's head are tracked.
It is an object of the present invention to provide hands-free cursor positioning for a data terminal.
It is another object to provide communication with a data processing system by way of operator head motion through a data terminal.